The manufacture of end mills for use with positive rake inserts has traditionally been accomplished by plunge cutting gullets in a direction generally tangent to the cylindrical periphery of a tool blank to a point where the plunge forms a 90 degree angle with respect to an imaginary line extending radially from the rotational axis. A disadvantage of this method is that an unnecessarily large amount of tool stock is removed thereby weakening the rises carrying the inserts. In addition, the length of the plunge, which forms the chip gullet and insert pocket, necessarily dictates the number of inserts which can be mounted peripherally. An end mill which utilized a shorter plunge length or chord while providing a positive rake cutting edge would therefore be a considerable advance in the art of cutting tools.
Another object of the present invention is to provide an end mill tool with enhanced pocket and body strength.
A further object of the present invention is to provide an end mill tool with chip gullets of reduced diameter which generate tight chip curls.
A further object of the present invention is to provide an end mill having an improved number of effective cutting teeth where the indexable inserts have positive axial rake cutting edges.
Another object of the present invention is to provide an end mill tool for cutting difficult to machine metals with ceramic inserts having positive rake cutting edges.